1. Field of the Invention
The present invention relates to paper machines, and, more particularly, to a broke handling system for handling a fiber web produced by a paper-making machine during a sheet break.
2. Description of the Related Art
A paper-making machine receives a prepared fiber suspension and produces a fiber web, such as a paper web. The paper-making machine includes a plurality of sequentially arranged traveling surfaces such as a wire, felt or water impervious belt (generically referred to herein as a belt) which carry the fiber web from one end of the machine to the other end.
Although not desirable, the traveling fiber web will occasionally break during operation of the paper-making machine (known as a xe2x80x9csheet breakxe2x80x9d). Sensors may be utilized within the paper-making machine to detect a sheet break. When a sheet break occurs, the fiber web is directed to an area below the paper-making machine where it is manually collected by workers and either discarded or returned to a pulping system for reuse. For example, the fiber web may be directed to an area below the paper-making machine through a space where the fiber web is typically transferred from one belt to another. Since a fiber web may be approximately 10 meters wide and can travel at speeds up to approximately 6,000 feet per minute, the amount of fiber web which is discarded in an area below the paper-making machine can be substantial before the machine is stopped or the fiber web is reestablished in the paper machine. A sheet break therefore not only is undesirable in terms of reduced throughput rate, but also requires unnecessary labor on the part of attending workers.
What is needed in the art is a system for effectively and efficiently handling and/or repulping a fiber web upon occurrence of a sheet break in a paper-making machine.
The present invention provides a paper machine with an under-machine handling system having a cutting device which cuts a fiber web into a plurality of smaller pieces upon occurrence of a sheet break. The smaller pieces can be easily transported to a number of broke fiber recovery devices or systems for reuse in the paper machine.
The invention comprises, in one form thereof, a paper machine having a traveling belt for carrying a fiber web. A cutting device is disposed below the belt for cutting the fiber web into smaller pieces. The cutting device has an inlet and an outlet. A guiding device guides the fiber web from the belt to the inlet of the cutting device. A pulper is connected with the outlet of the cutting device for receiving the smaller pieces of fiber web from the cutting device. The traveling belt may be in the form of, e.g., a wire, felt or water impervious belt. The cutting device may be in the form of, e.g., a shredder, fluffer, water jet cutter, laser cutter and/or roll cutter.
An advantage of the present invention is that the fiber web is cut into a plurality of smaller pieces before being fed into a broke fiber recovery device, thereby providing a more effective and flexible system. For example, for a pulper used as a broke recovery device the inlet to the pulper occupies less space, and thus the overall size of the pulper may be reduced.
Yet another advantage is that cutting the fiber web into smaller pieces allows less energy to be used by the pulper during the repulping process.
A still further advantage is that the cut smaller pieces can be transported directly into a high consistency pulper and/or high consistency pump, thereby reducing the amount of water used during the pulping process.
A still further advantage is that the cut smaller pieces can be introduced directly into a blower tank or baler for subsequent transfer to a pulper, thereby further reducing the amount of water consumed during the pulping process.
Another advantage is that by cutting the fiber web into smaller pieces, the size of the pulping system can be reduced, thereby resulting in less physical space requirements and capital investment costs.
A still further advantage is that since the pulping system is smaller in size as a result of the cut smaller pieces, the amount of space occupied by the pulping system under the papermaking machine is less which results in more space for other equipment.